Page:NIOSH Manual of Analytical Methods - 2522.pdf/2

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NITROSAMINES: METHOD 2522, Issue 2, dated 15 August 1994 - Page 2 of 4 EQUIPMENT:

REAGENTS: 1. 2. 3. 4. 5.

6. 7. 8.

Dichloromethane, reagent grade. Methanol, reagent grade. Nitrogen, purified. Oxygen, purified, 99.99%. Standard solutions of N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosodibutylamine, N-nitrosodipropylamine, N-nitrosomorpholine, N-nitrosopiperidine, N-nitrosopyrrolidine. Eluent, 3:1 (v/v) dichloromethane/methanol. Air, filtered, compressed. Ozone, purified 99.99%.

1.

2. 3.

4. 5. 6.

See SPECIAL PRECAUTIONS.

7. 8. 9. 10.

Sampler: Commercially available tubes (Thermedics Detection, Inc., 220 Mill Rd., Chelmsford, MA 01824, 508/251-2000). Personal sampling pump, 0.2 to 2 L/min, with flexible tubing. Gas chromatograph equipped with thermal energy analyzer (TEA), integrator and column (page 2522-1). Vials, glass, 2-mL, PTFE-lined crimp caps. Pipets, various sizes for preparing standards. Syringes, 1-, 5-, 10-, 25-, and 100-µL readable to 0.1 µL. Volumetric flasks, 10-mL. Gloves for safe handling of toxic chemicals. Syringe, glass, 5.0-mL, with male Luer adapter. Needle, industrial blunt, 20-gauge with female luer adapters.

S P E C I A L P R E C A U T I O N S : N-nitrosodimethylamine is an OSHA-regulated SAMPLING: carcinogen. Other nitrosamines are suspected carcinogens and are very toxic. Handle samples 1. Calibrate each personal sampling pump and standards in a well-ventilated hood or glove with a representative sampler in line. box. 2. Remove the Thermosorb/N tube from the foil pouch. Save the pouch. 3. Remove the red end caps from the inlet and outlet ports. Store red caps on the Thermosorb/N tube in the brackets under the "AIR IN" sign. 4. Label the Thermosorb/N tube with the peel-off "AIR SAMPLER" label provided on the foil pouch. 5. Attach the Thermosorb/N tube to the sampling pump with flexible tubing. 6. Sample at an accurately known flow rate between 0.2 and 2 L/min for a total sample size of 15 to 1000 L. 7. After sampling, detach the sampler from the pump. 8. Replace the red end caps on the inlet and outlet ports of the sampler. 9. Replace the Thermosorb/N tube in the foil pouch. Fold the pouch and seal it with the clip provided and pack securely for shipment.

SAMPLE PREPARATION: 10. 11. 12. 13. 14. 15.

Remove the sampler from the foil pouch. Label analysis vial with the label from the Thermosorb/N air sampler. Remove the red end-caps, store them in the bracket provided with the tube. Attach a syringe needle to the male Luer fitting of the Thermosorb/N tube. Attach a syringe barrel containing eluent to the female Luer fitting of the Thermosorb/N tube. Elute by "backflushing" the Thermosorb/N tube with 2.0 mL of eluent. Collect the effluent in the labeled vial. NOTE: The optimum elution rate is 0.5 mL/min.

CALIBRATION AND QUALITY CONTROL:

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94